Tester Site
November 27, 2020
Please Note This website is a tester for page layout and data visualization for the Lipp Lab COVID Wastewater monitoring project. The data on this page are not peer-reviewed or finalized for public release and thus should not be interpreted as such. If you are interesed in viewing the final data from this project please visit this website.
This dashboard provides weekly updates of SARS‑CoV‑2 (the virus that causes COVID‑19) levels in wastewater for Athens-Clarke County (ACC). Wastewater sampling can detect viruses that may be shed in feces from infected people within an entire community, including those that are presymptomatic and asymptomatic. This offers a method of estimating trends in community-scale circulation of COVID‑19 that does not rely on clinical or surveillance testing of individuals. Although we cannot currently use wastewater-based testing to estimate a specific number of people infected in a community, it can be used to understand trends and to anticipate potential increases in cases.
Navigating this site:
• Data Trends: Total viral load and trend analysis for the combined ACC area
• Individual Plants: Viral load and trend analysis for each plant and associated service area
• All Data: Concentration of SARS‑CoV‑2 gene targets by date and treatment plant
• Research Overview: Details on methods and approach
Data Trends
The trendlines below reflect the estimated total viral load of SARS‑CoV‑2 in the combined sewershed of Athens Clarke County (the service area for all three plants) (top chart) over time. The daily number of newly reported COVID‑19 cases in Athens-Clarke County (purple bars) appear alongside the 7-day moving average of new cases (yellow line) (bottom chart). We are using these data to estimate how changes in the concentration of SARS‑CoV‑2 in wastewater may reflect the community trends of circulating COVID‑19 infections.
Note about chart and methods.
The viral load is estimated for both the N1 (green) and N2 (orange) gene targets (concentration of gene copies per liter x total flow in liters). Both genes target the SARS‑CoV‑2 genome but have slight differences in how they perform in our tests; therefore, we are providing both to give a better idea of the range of viral numbers. The data trend lines were calculated using locally estimated scatterplot smoothing (LOESS, span = 0.6). The error associated with these estimates (the 95% confidence interval) is displayed as the shaded area. Vertical dashed lines indicate significant events that may affect local public health: June 24, 2020 Georgia continues broad reopening, including bars and restaurants; July 9, 2020 Athens-Clarke County implements mask mandate.; August 20, 2020 classes begin at the University of Georgia; October 3, 2020 the university hosted its first home football game for the fall season.
Weekly Data Update
Updated every Thursday
Please Note: We strive to get results for each week’s sampling updated by 5:00 pm on Thursday however, to ensure quality of data occasional delays in the update may occur. We will post updated data as soon as we are able.
Testing
This week’s viral load score is red.
Viral concentrations have been increasing this week.
This week’s viral load score is yellow.
Viral concentrations have been steady this week.
This week’s viral load score is green.
Viral concentrations have been decreasing this week.
By quartile-total log SARS CoV-2 Copies
green (lower 25%) = less than 10.81 for N1 and 10.68 for N2
yellow (mid 50%) = 10.81 to 13.15 for N1 and 10.68 to 13.22 for N2
red (upper 25%) = greeater than 13.15 for N1 and 13.22 for N2
Nov 23 & 25
This week’s viral load score is red.
Viral concentrations have been increasing this week.
November 23
The levels of SARS‑CoV‑2 have increased approximately 10-fold from the previous sampling period (November 18, 2020). It is too to soon to predict if the increase in SARS‑CoV‑2 levels indicates in increase in transmission. If there is increased transmission, we would expect to see this same trend in our next sampling period (November 25, 2020).
The 7-day running average of newly reported cases has remained stable for the last 2 weeks (ranging between 27 and 32 new cases per day).
November 25
The Wednesday data update will be delayed until Monday November 30. We apologize for the inconvenience.
Nov 16 & 18
November 16
For the Monday sample this week (collected between 6:30 am Sunday 11/15 and 6:30 am Monday 11/16). We observed increased concentrations of SARS‑CoV‑2 at all plants based on the N1 gene; concentrations (copies per L) increased by >80% since the November 11 sample. However, the N2 gene target was below the limit of detection for all plants. We observed a similar divergence on 11/04 and we are continuing to evaluate the performance of both assays. On balance, the data suggest a slight but consistent increasing trend.
The 7-day running average of daily reported cases in Athens-Clarke County is 31 as of 11/17, similar to that reported last week, after several weeks of reported cases in the low 20s.
November 18
There was little change in the SARS‑CoV‑2 concentrations and total load for the sample collected on 11/18. Levels were comparable to those measured on 11/16 and in the previous week. Good agreement was observed in the estimation of both the N1 and N2 gene targets.
Daily reported cases remain at a seven-day average of 32.
Nov 9 & 11
This week, 24-hour composite samples were collected on Monday 11/9 and Wednesday 11/11. Total daily load estimates for the week show stable to increasing levels. WRF A loads increased modestly on 11/9 with little change by 11/11. At WRF B, estimated loads declined to the limit of detection on 11/9 but increased to >500,000 copies per liter for both gene targets by 11/11. WRF C loads increased through both sampling dates. Of note, both gene targets were detected this week, with notable increases in the N2 gene (which was largely below the limit of detection last week).
The 7-day running average of daily reported cases (PCR confirmed) in Athens-Clarke County has increased slightly in the last week to an average of 31 cases per day as of 11/12.
Nov 2 & 4
Site update announcement:
Beginning November 2, 2020, data from all three plants is being reported on this site. Data summaries have been updated to include the third plant (WRF C) back to July 5, 2020. Therefore, charts for ‘data trends’ and ‘all data’ may vary slightly from previously posted reports because of this inclusion; although, in part because WRF C is small compared to the other two plants, trends changed little with this update.
Going forward, we will begin sampling twice weekly at the three WRFs with support from Athens-Clarke County. We will update this site with any anticipated changes in timing of our data reporting.
November 2 & 4 data update: This week, we are reporting concentrations of SARS‑CoV‑2 in wastewater collected from two sampling events (~6:30 am Sunday Nov 1 to ~ 6:30 am Monday Nov. 2 and ~6:30 am Tuesday Nov. 3 to ~6:30 am Wednesday Nov. 4, 2020). The increased sampling frequency is intended to improve the resolution of our data.
This week, there was a notable difference in the trends based on the two gene targets, with viral gene copies attributed to the N1 gene increasing slightly (especially at WRF B) or staying steady and viral gene copies attributed to the N2 gene declining (with most samples at or below the limit of our detection). Detection rates of the two genes can vary, especially in wastewater; therefore, it is important to consider results of these targets together. In combination, we think that these results suggest SARS‑CoV‑2 loads are stable or may be declining
The 7-day running average of reported cases (PCR confirmed) in Athens-Clarke County has remained steady at 22 - 24 new cases per day.
Oct 27
Concentrations of SARS‑CoV‑2 in Athens-Clarke County wastewater are comparable to those reported during the previous week (October 20, 2020). Concentrations are also similar between the two plants. These data suggest that there may be persistent viral shedding throughout the community. Reported cases in Athens-Clarke County have been stable over the past three weeks, with a 7-day running averages of 20-24 cases per day.
Oct 20
SARS‑CoV‑2 concentrations in Athens-Clarke County wastewater showed a consistent upward trend this week. WRF A continued its increase from the prior week with concentrations reaching as high as 1 million copies per L. Concentrations at WRF B increased from the below the limit of detection to >300,000 copies per L. The continued upward trends may suggest changes in viral shedding within the community.
Reported cases in Athens-Clarke County have been stable over the week, with a 7-day running average of 20-30 cases per day.
Oct 13
Trends in SARS‑CoV‑2 concentrations in Athens wastewater were split this week between the two sampled plants. During the collection period (Oct 12 – 13), viral RNA concentrations at WRF B declined to at or below the limit of detection. However, levels at WRF A increased to >500,000 copies per L, after declining to near the limit of detection the prior week. It is too early to know if the increased SARS‑CoV‑2 signal at WRF A is indicative of possible uptick in transmission or due to inherent variability in sample collection. If there is increased transmission, we would expect to see the trend in wastewater continue next week as well as an increase in reported cases.
Reported cases in Athens-Clarke County have remained stable for the last 2 weeks (7-day running average between 21 and 24 new cases per day.
Oct 6
Levels of SARS‑CoV‑2 continue to decrease in wastewater samples collected from Athens-Clarke County. These results are consistent with the decrease in the number of newly-reported cases over the past two weeks.
It is important to note that the levels of SARS‑CoV‑2 virus have decreased to or at the limit of detection for our current method. Our theoretical limit of detection is approximately 3,570 copies/L. Below this concentration, viruses may be not be detected or quantified with accuracy.
Sept 29
Overall SARS‑CoV‑2 concentrations continued to decline in sewage reaching Athens’s WRFs, in line with decreasing reported cases in Athens-Clarke County. The decline was especially evident at WRF A, where levels were at or below the limit of detection for our methods. However, concentrations at WRF B were virtually unchanged from last week.
With our current process, we cannot accurately detect virus concentrations below about 3,000 copies per L. Therefore, we cannot assume that a sample that is ‘below the limit of detection’ is negative for SARS‑CoV‑2, rather it may be at some level that we cannot accurately determine with our current method. Our lab is evaluating different detection options that may improve detection during times with lower levels of circulating virus.
Sept 22
Concentrations of SARS‑CoV‑2 declined this week in wastewater collected from both WRFs. Average levels remain above 100,000 copies/L. This decline is consistent with declines in reported cases in Athens-Clarke County.
Sept 15
This week, the level SARS‑CoV‑2 continued to exceed 1 million copies of virus per liter of sewage. While the 7-day running average of new cases has declined in Athens-Clarke County, there were no significant changes in the level of SARS‑CoV‑2 virus in wastewater, compared to those observed on September 9, 2020.
Sept 8
This week, levels of SARS‑CoV‑2 for both targets at both plants continued to exceed 1 million copies of virus per liter of sewage. Average values were similar to concentrations from the prior week (September 1, 2020) with virtually no change in the average levels at WRF B and a 6% reduction at WRF A.
An important note about sample collection this week was that it occurred over the Labor Day holiday and may explain the slight reduction in viral concentration at the WRF A plant. Samples were collected between ~6:30 am Monday through 6:30 am Tuesday. The volume of wastewater flowing into WRF A decreased from 5.73 million gallons on September 1, 2020 to 4.96 million gallons on September 8, 2020. The collection area for WRF A includes the UGA main campus and Downtown Athens. We suspect that this week’s data point reflects the real-time effect of population movement on viral levels in wastewater. In other words, a closed campus and likely large number of people traveling reduces the input. Samples collected on a particular day reflect the inputs of that day and not necessarily the entire week.
Our trend analysis suggests a continued elevation in total viral load (see data trends tab).
Daily reported cases in Athens-Clarke County continue to rise, now reaching a 7-day moving average of 126.1 new cases per day.
Sept 1
This week continues the trend of the past month with SARS‑CoV‑2 concentrations increasing in wastewater. Levels increased to their highest point since the beginning of data collection with average concentrations for both plants and both targets exceeding 3 million copies of virus per liter of sewage, approximately 10-fold higher than the prior week. Daily reported cases in Clarke County also continued to rise reaching a 7-day moving average of >74 cases per day.
August 2020
Aug 25
SARS-CoV-2 concentrations in Athens-Clarke County wastewater increased slightly in this week’s samples (reaching >900,000 copies of the virus per liter of sewage). This moderate increase continues the upward trend observed over the prior three weeks. Reported cases have remained steady through the week (8/18 - 8/25/2020) averaging ~30 new cases per day.
Aug 28
On August 18, 2020, the concentration of SARS‑CoV‑2 increased to over 100,000 copies per liter for both gene targets. This uptick is somewhat reflected in the daily reported cases for Athens-Clarke county and may indicate further increases in the coming weeks.
Furthermore, this week marks the return of approximately 30,000 undergraduate students to the UGA main campus for the start of the fall semester.
Prior to Aug 18, 2020
Weekly analyses of SARS‑CoV‑2 in sewage began June 16, 2020, at which time concentrations were below the current method limit of detection and new cases were reported at <10 per day. Reported cases began to increase to >20 per day in late June and SARS‑CoV‑2 concentration increased to up to 10 million viral copies per liter. Sewage concentrations were steady through mid-July inline with newly reported cases averaging 35 per day. Beginning July 21, 2020 SARS‑CoV‑2 concentrations in sewage began to decline through early August, while concurrent case report remained high. We suspect that this decline possibly preceded the decline in cases noted in late August, which may be due to lags in testing results and case reporting.
Since August 4, 2020 SARS‑CoV‑2 concentration has steadily increased for both the N1 and N2 gene targets. This suggests that sewage concentrations may be a leading indicator for new cases in the community, but more data collection and monitoring of delays in testing reports will be needed to confirm this trend.
Individual Plants
Three plants service the Athens-Clarke County region. WRF A serves the largest portion of the community (including all of UGA main campus and downtown Athens), followed by WRF B (including areas west of Milledge Ave.), and WRF C (including Athens Eastside). Total capacity at WRF C is substantially smaller than the other two plants; this plant also receives periodic waste from pumped septic system and ‘port-o-potties’, which may lead to increased variability over time. Load and trends over time are shown for each service area. Trend analyses follow the same procedure as noted in ‘Data Trends’ tab.
Sewershed Map
Sewershed map of Athens-Clarke County
WRF A
WRF B
WRF C